1. Field of the Invention
The present invention relates to communications networks in general and in particular to devices used in such networks to interconnect multiple outlets or ports to a single network lobe.
2. Prior Art
The proliferation of computers, work stations, servers, etc. (collectively called Data Terminal Equipment, DTE) creates a requirement for additional ports which interconnect such DTEs to a communications network. The communications network provides the data highway interconnecting the DTEs so that one DTEs may communicate with others.
Among the different types of communications networks is the Local Area Network (LAN) which is used to interconnect DTEs in a building or limited geographical area such as a college campus, etc. The LANs are also divided into different types. Among the different types of LANs is the well-known ring LAN. The ring LAN is a serial network in which DTEs are sequentially connected to a closed loop transmission media. The information to be transmitted on the network is packaged into packets by a source DTE and is sequentially transmitted by DTEs located between the source DTE and a receiving DTE.
The interconnection of a DTE to the closed loop transmission media is effectuated by data connectors positioned in the selected walls of an office, etc. The wiring system forming the LAN is located behind the walls and ceilings of the office. The typical LAN installation provides a single outlet for each office. Often times the need arises for a plurality of outlets in an office or other area where the original wiring provides one or a limited number of connections into the closed loop transmission media.
The obvious way of providing additional outlets is to interconnect the additional outlets to an available outlet located in the office or other areas. The prior art, such as U.S. Pat. Nos. 5,101,405; 4,905,230; 4,862,158; 4,757,497 and 4,701,630 disclose devices and techniques for attaching multiple DTEs to a single outlet in an office (U.S. Pat. No. 4,701,630) or multiple DTEs to a single lobe of the LAN (U.S. Pat. No. 4,862,158).
Even though the prior art provides additional outlets in an office or other work areas, the mechanisms which provide the expansion are complicated and often times require work on the wiring system located behind the office walls and/or ceilings. Needless to say, accessing the original wiring systems are expensive and sometimes access to such systems is impossible.
Most LANs are designed to conform with standards such as the IEEE 802.5 Standard for Token Ring LAN. The standards set forth protocols (including timing signals) and formats which are required to transmit or receive information from the network. Usually, if multiple DTEs are connected to a single lobe or outlet, the timing and other protocols from the lobe or outlet is altered and the network is no longer in compliance with the standard. To overcome this problem, corrective circuitries and techniques are required on the port or in the lobe expansion mechanism in order to comply with the selected standard.